This invention relates to the preparation of a class of polymeric products from the reaction of diphenylamine with at least one of the following difunctional alkylating agents: 1,4-di-.alpha.-alkyl-alkenylbenzene, 1,4-di-.alpha.-hydroxyalkylbenzene, 1,3-di-.alpha.-alkyl-alkenylbenzene or 1,3-di-.alpha.-hydroxyalkylbenzene. In particular, the present invention relates to reacting the diphenylamine with the difunctional alkylating agent in the presence of an acid catalyst to produce polymeric compounds useful as an antioxidant for the protection of oxidizable organic polymers.